Earthworm avoidance tests

Based on the fact that organisms have the ability to avoid unfavorable conditions, the avoidance tests with earthworms have been used as an important tool to detect contaminants present in soil. Being ecologically relevant, quick and cost-effective, these bioassays have high sensitivity compared to conventional acute and chronic tests. Earthworm avoidance tests were performed in an inter-laboratory ring test of waste in accordance with ISO guideline No 17512-1 to evaluate the usefulness of this type of bioassays in waste characterization. Concentration gradients of three test wastes (INC, SOI and WOO) were tested using the artificial OECD soil as control. The species Eisenia fetida and Eisenia andrei were used as test organisms. A total of 12 avoidance tests were performed by four laboratories. The results obtained proved the higher sensitivity of this type of bioassay compared to tests using other terrestrial organisms (in particular, the earthworm acute test). Although all three wastes induced an avoidance behavior, the WOO treatments were the most avoided. © 2009 Springer-Verlag New York.